A facility in the field of Factory Automation (FA) is generally achieved by combining multiple types of devices. The devices constituting the facility in the FA field are connected to programmable controllers, each of which is a control apparatus integrating a control process and an information process. The programmable controllers are distributed in the facility in the FA field. The distributed programmable controllers are synchronized on the basis of a trigger signal input with a fixed synchronization period from a communication bus (see Patent Literature 1).